Patent US3904652A successfully refreshed from Google Patents.
US3904652A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recycle process for oxidation of n-butane to maleic anhydride
Assignee: BP Corp North America Inc
•
Filing: 1972-11-16
•
Granted: 1975-09-09
•
Expires: 1992-11-16
Abstract
Abstract In the oxidation of butane to form maleic anhydride over a phosphorus-vanadium-oxygen complex catalyst, improved yields and processing advantages are obtained by using low oxygen concentrations and recycling the off-gas from the scrubbing operation.
Inventors
- 👤 Marshall E Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:09
CPC Classifications
B; B01; B01J; B01J31/00; B01J31/16; B01J31/22; B01J31/2204; B01J31/2208; B01J31/2226; B01J31/18; B01J31/1845; B01J31/26; C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/215; B01J2531/00; B01J2531/50; B01J2531/56
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
114 words
IN A PROCESS FOR THE PREPARATION OF MALEIC ANHYDRIDE WHEREIN N-BUTANE IS OXIDIZED IN A REACTION ZONE IN THE PRESENCE OF A PHOSPHOROUS-VANDADIUM-OXYGEN COMPLEX CATALYST CONTAINING ONE OR MORE METAL ACTIVATORS SELECTED FROM THE GROUP CONSISTING OF ZINC, COPPER, BISMUTH AND LITHIUM, THE IMPROVEMENT WHICH COMPRISES: MAINTAINING, IN THE REACTION ZONE, THE N-BUTANE CONCENTRATION ABOVE 1.7% OF THE FEED, THE OXYGEN CONCENTRATION FROM 3-13% AND THE INERT GAS CONCENTRATION FROM 70-95%, CONVERTING FROM 30 TO 70% OF THE NBUTANE, WITHDRAWING A REACTOR EFFLUENT FROM SAID REACTION ZONE CONTAINING MALEIC ANHYDRIDE, OXIDES OF CARBON AND UNREACTED BUTANE, SEPARATING THE MALEIC ANHYDRIDE, AND RECYCLING A MAJOR PORTION OF THE REMAINING REACTOR EFFLUENT TO THE REACTION ZONE.
Claim 2
Dependent Claim
114 words
IN A PROCESS FOR THE PREPARATION OF MALEIC ANHYDRIDE WHEREIN N-BUTANE IS OXIDIZED IN A REACTION ZONE IN THE PRESENCE OF A PHOSPHOROUS-VANDADIUM-OXYGEN COMPLEX CATALYST CONTAINING ONE OR MORE METAL ACTIVATORS SELECTED FROM THE GROUP CONSISTING OF ZINC, COPPER, BISMUTH AND LITHIUM, THE IMPROVEMENT WHICH COMPRISES: MAINTAINING, IN THE REACTION ZONE, THE N-BUTANE CONCENTRATION ABOVE 1.7% OF THE FEED, THE OXYGEN CONCENTRATION FROM 3-13% AND THE INERT GAS CONCENTRATION FROM 70-95%, CONVERTING FROM 30 TO 70% OF THE NBUTANE, WITHDRAWING A REACTOR EFFLUENT FROM SAID REACTION ZONE CONTAINING MALEIC ANHYDRIDE, OXIDES OF CARBON AND UNREACTED BUTANE, SEPARATING THE MALEIC ANHYDRIDE, AND RECYCLING A MAJOR PORTION OF THE REMAINING REACTOR EFFLUENT TO THE REACTION ZONE.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein the inert gas is nitrogen.
Claim 4
Dependent Claim
30 words
The process of claim 1 wherein a portion of said remaining reactor effluent is purged so as to maintain an equilibrium concentration of the oxides of carbon in the system.
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein pure oxygen is introduced into the reaction system and admixed with an inert gas and the recycle stream.
Claim 6
Dependent Claim
30 words
The process of claim 1 wherein a combination of pure oxygen and atmospheric air are introduced into the reaction system and admixed with an inert gas and the recycle stream.
Claim 7
Dependent Claim
15 words
The process of claim 1 wherein the reaction pressure is from 15 to 100 p.s.i.a.
Claim 8
Dependent Claim
39 words
The process of claim 1 wherein the catalyst comprises about 0.5 to about 5 atoms of phosphorus for each atom of vanadium and is activated with from 0.05 to 0.35 atoms of an activator for each atom of vanadium.
Claim 9
Dependent Claim
10 words
The process of claim 7 wherein the activator is zinc.
Claim 10
Dependent Claim
20 words
The process of claim 7 wherein there is one to two atoms of phosphorus present for each atom of vanadium.
References Cited (Backward Citations)
US3293268A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |